LONDON (AFP) - Two British troops were killed in southern Afghanistan, the Ministry of Defence announced Thursday, both outside the ongoing NATO assault against Taliban insurgents. An airman died in an explosion late Wednesday, while a soldier was killed by small arms fire on Thursday. The soldier from A Company, 4th Battalion The Rifles, was shot and killed near Sangin in northern Helmand Province. He was on a foot patrol, part of ongoing operations to protect the people of Sangin from insurgents, when his patrol was fired on, a spokesman said. Meanwhile the airman from 2 Squadron, Royal Air Force Regiment, was serving as part of the Kandahar Airfield Defence Force. He died from wounds received during a blast while on a vehicle mounted patrol. He was on a mobile patrol in an area about four kilometres north of Kandahar Airfield when the explosion happened, a military spokesman said.